The Husqvarna ECA850 is a professional-grade curved shaft edger attachment designed for the Husqvarna LK and iLK series Combi power heads. Featuring a 24 mm shaft and 7-tooth spline, it is compatible with gas models like the 129LK, 525LK, and 535LK, as well as battery units like the 325iLK. This attachment is not compatible with standard 128LD or 129LD homeowner models.